Study of bimetallic effect in a GaAs cantilever beam of power sensor microsystem

A bimetallic effect in a 2-/spl mu/m-thick GaAs cantilever beam of power sensor microsystem (PSM) is studied using both the microscopic laser optical interferometry and laser optical reflectance measurement. The cantilever beam deflections induced by the different thermal expansion of the GaAs cantilever layer and the top device metallic leads are sensed at different power dissipations in the PSM heater. The key transfer characteristics of the PSM are found. The cantilever bimetallic effect is also considered to be used for the electrical power sensing.